Abstract

Peer toPeer (P2P) is one of themost popular technology which paved a way to new structures in many applications including content searching, file sharing etc. On the other hand, inclusion of a few malicious peers, the entire network could be disrupted without proper security measures. This paper presents a very simple but an effective security mechanism for gossip based P2P networks. In the proposed protocol, each gossiping node observes its peers closely to ensure that no malicious nodes will actively participate in the gossip protocol. To achieve this, each peer builds trust information about other nodes in the system and exchanges with its neighbours. Using the trust information, each node is able to identify and blacklist malicious nodes in its view. Thus, each node gossips only with nodes it deems as non-malicious. The efficiency of the proposed protocol is far ahead of existing security protocols such as TooLate. Our simulation results show the effectiveness of the proposed work.